• Journal of the Chungcheong Mathematical Society
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• v.1 no.1
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• pp.71-76
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• 1988

For each continuous convex function ${\phi}$ defined on an open convex subset $A_{\phi}$ of a Banach space X, if we define a positively homogeneous sublinear functional ${\sigma}_x$ on X by ${\sigma}_x(y)=\sup{\lbrace}f(y)\;:\;f{\in}{\partial}{\phi}(x){\rbrace}$, where ${\partial}{\phi}(x)$ is a subdifferential of ${\phi}$ at x, then we get the following characterization theorem of Gateaux differentiability (weak Asplund) sapce. THEOREM. For every ${\phi}$ above, $D_{\phi}={\lbrace}x{\in}A\;:\;\sup_{||u||=1}\;{\sigma}_x(u)+{\sigma}_x(-u)=0{\rbrace}$ contains dense (dense $G_{\delta}$) subset of $A_{\phi}$ if and only if X is a Gateaux differentiability (weak Asplund) space.

• Kyungpook Mathematical Journal
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• v.28 no.1
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• pp.23-34
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• 1988

A version of Ascoli's Theorem (equating compact and equicontinuous sets) is presented in the context of convergence spaces. This theorem and another, (involving equicontinuity) are applied to characterize compact subsets of quasi-multipliers of a $C^*$-algebra B, and to characterize the compact subsets of the state space of B. The classical Ascoli Theorem states that, for pointwise pre-compact families F of continuous functions from a locally compact space Y to a complete Hausdorff uniform space Z, equicontinuity of F is equivalent to relative compactness in the compact-open topology([4] 7.17). Though this is one of the most important theorems of modern analysis, there are some applications of the ideas inherent in this theorem which arc not readily accessible by direct appeal to the theorem. When one passes to so-called "non-commutative analysis", analysis of non-commutative $C^*$-algebras, the analogue of Y may not be relatively compact, while the conclusion of Ascoli's Theorem still holds. Consequently it seems plausible to establish a more general Ascoli Theorem which will directly apply to these examples.

• Korean Institute of Interior Design Journal
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• v.16 no.6
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• pp.172-180
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• 2007

As library have become changed. Beyond conventional simple functions such as data storing and recording, the functions of modern public libraries are expended to various directions, for example functions of encouraging residents to utilize information and participate in cultural activities and also a function of life-long education, resulting in playing a role as complex space. As the role of public libraries changes into a complex one, spatial planning reflecting this change is required. Spatial arrangements, furniture arrangements and interior images in 12 public libraries in Seoul were analyzed. As a result of the study, it was found that in spatial arrangements, many public libraries linked spaces by functions. Furniture arrangements have been changing from the closed arrangement to the open arrangement. Interior images were identified as static and simple except digital information space. Accordingly, public libraries have became needed to play a proper role of community facilities for local residents by planning furniture arrangements and conducting interior designs taking characteristics of many different users into consideration.

• Journal of the Korean Institute of Landscape Architecture
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• v.23 no.2
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• pp.44-62
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• 1995

This study investigated the landscape space of Chosun Dynasty pavilions in the Sang-ju Region. Five renowned pavilions were selected for study by Phenomenological and IDRISI (4.1) S/W. The results were as follows ; Pavilions were erected for studying cultivating moral sense admiring the view relieving illness and commemorat memoring people. A total of 248 pavilions were erected in the Sang-ju Region between 1392 and 1895 AD, most of them duing he golden age from 15001670 AD. Pavilions and open space were composed in harmony with nature borrowing natural landscape features. Landscape characteristics were analysised with IDRISI(4.1) S/W; pavilions were ma711y located at the bottom of a mountain with stream The Inner garden was formed by a fence and Lagerstroemia indica or a few trees. The Outer garden was formed by mixed stands of Pinus dentsiflora, Zelkowa serreta, Acer formosum and well conserved natural vegetation.

• Bulletin of the Korean Mathematical Society
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• v.53 no.2
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• pp.531-540
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• 2016

In this work, we introduce the complete Riemannian manifold $\mathbb{F}_3$ which is a three-dimensional real vector space endowed with a conformally flat metric that is a solution of the Einstein equation. We obtain a second order nonlinear ordinary differential equation that characterizes the helicoidal minimal surfaces in $\mathbb{F}_3$. We show that the helicoid is a complete minimal surface in $\mathbb{F}_3$. Moreover we obtain a local solution of this differential equation which is a two-parameter family of functions ${\lambda}_h,K_2$ explicitly given by an integral and defined on an open interval. Consequently, we show that the helicoidal motion applied on the curve defined from ${\lambda}_h,K_2$ gives a two-parameter family of helicoidal minimal surfaces in $\mathbb{F}_3$.

• Structural Engineering and Mechanics
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• v.69 no.2
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• pp.121-129
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• 2019

The present study investigates the propagation of shear waves in a composite structure comprised of imperfectly bonded piezoelectric layer with a micropolar half space. Piezoelectric layer is considered to be initially stressed. Micropolar theory of elasticity has been employed which is most suitable to explain the size effects on small length scale. The general dispersion equations for the existence of waves in the coupled structure are obtained analytically in the closed form. Some particular cases have been discussed and in one particular case the dispersion relation is in well agreement to the classical-Love wave equation. The effects of various parameters viz. initial stress, interfacial imperfection and micropolarity on the phase velocity are obtained for electrically open and mechanically free system. Numerical computations are carried out and results are depicted graphically to illustrate the utility of the problem. The phase velocity of the shear waves is found to be influenced by initial stress, interface imperfection and the presence of micropolarity in the elastic half space. The theoretical results obtained are useful for the design of high performance surface acoustic devices.

• Journal of the Architectural Institute of Korea Planning & Design
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• v.35 no.11
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• pp.3-12
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• 2019

This study is concerning on the Space Modification and Facilities Characteristics of the Busan Exported-cow Quarantine Service Station(1909) before and afrter on the limits of 1945. For on this purpose, National Archives & Records Service(DJB0002115), field survey, documents records and modern aged map were analysised by each period phases, 1909, 1924, 1946, 1951 and now so on. At results on this study is the discovery on the meaning of this placeness, Space Modification and Facilities Characteristics till now before the 120 years ago. And this place has been comprehenive meaning unique dwelling form and almost rarely existing refuge village of Korea War in Korea.

• KEPCO Journal on Electric Power and Energy
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• v.7 no.2
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• pp.255-261
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• 2021

This paper proposes impedance-based stability analysis of DC-DC boost converters, where a harmonic state space (HSS) modeling technique is used. At first, the HSS model of the boost converter is developed. Then, the closed-loop output impedance of the converter is derived in frequency domain using small signal modeling including frequency couplings, where harmonic transfer function (HTF) matrices of the open-loop output impedance, the duty-to-output, and the voltage controller are involved. The frequency response of the output impedance reveals a resonance frequency at low frequency region and frequency couplings at sidebands of switching frequency which agree with the simulation and experimental result.

• International Journal of High-Rise Buildings
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• v.12 no.3
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• pp.263-272
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• 2023

Role of architecture should not be limited to function of providing an inhabitable space but also include urban and social role of its impact to the public and surrounding area. Role of landmark building should be further expanded beyond and landmark building speaks out its aesthetics with mass form and/or with its appearance of façade. With study of this project, idea of landmark building is shifted from vertical extrusion of the land to horizontal extrusion of large space from the face of building. It is a double extrusion creating large assembly space up in the air linking surrounding masses.

• Clinical Endoscopy
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• v.56 no.1
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• pp.23-37
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• 2023

Submucosal endoscopy or third-space endoscopy utilizes the potential space between the mucosal and muscularis layers of the gastrointestinal tract to execute therapeutic interventions for various diseases. Over the last decade, endoscopic access to the submucosal space has revolutionized the field of therapeutic endoscopy. Submucosal endoscopy was originally used to perform endoscopic myotomy in patients with achalasia cardia, and its use has grown exponentially since. Currently, submucosal endoscopy is widely used to resect subepithelial tumors and to manage refractory gastroparesis and Zenker's diverticulum. While the utility of submucosal endoscopy has stood the test of time in esophageal motility disorders and subepithelial tumors, its durability remains to be established in conditions such as Zenker's diverticulum and refractory gastroparesis. Other emerging indications for submucosal endoscopy include esophageal epiphrenic diverticulum, Hirschsprung's disease, and esophageal strictures not amenable to conventional endoscopic treatment. The potential of submucosal endoscopy to provide easy and safe access to the mediastinum and peritoneal spaces may open doors to novel indications and rejuvenate the interest of endoscopists in natural orifice transluminal endoscopic surgery in the future. This review focuses on the current spectrum, recent updates, and future direction of submucosal endoscopy in the gastrointestinal tract.